アプリケーション検索（技術資料）

UV/VIS detection is one of the most sensitive detection techniques in trace-level chromatography. Sometimes, however, spectrophotometric detection lacks sensitivity, selectivity or reproducibility and chemical derivatizations are required. By using Metrohm`s rugged and versatile flow-through reactor, single- or multi-step derivatizations can be done fully automatically, in either pre- or post-column mode at any temperature between 25…120 °C. The variable reactor geometry allows to adjust the reactor residence time of the reactants according to derivatization kinetics. The flexibility of the reactor is demonstrated by optimizing four widespread post-column techniques: the relatively slow ninhydrin reaction with amino acids and the fast derivatizations of silicate, bromate and chromate(VI).

This poster discusses results showing the influence of pH, temperature of the post-column reactor, eluent composition, and iodide concentration on the sensitivity of the triiodide method.

Drinking water which has been disinfected via the ozonation process can contain undesirable levels of bromate, a carcinogen, via oxidation of bromide in the raw water. Already several agencies including the World Health Organization have recommended concentration limits for bromate set in place to limit its risks to our health. Ion chromatography is mentioned in several analytical standards for the determination of disinfection byproducts (DBP) including bromate, such as EPA 300.1, 317.0, 321.8, 326.0, ASTM D6581, ISO 11206, and ISO 15061. Monitoring trace levels of bromate online means higher throughput and less time spent performing manual laboratory tests, and ensures quality drinking water is produced.

臭素は、飲料水浄化の際にオゾン処理によって生成される殺菌副産物です。これは人体に対する発がん性が疑われるため、望ましいものではありません。水道事業者、ならびにボトル入りミネラルウォーターの製造者は、各公的機関が定めた限界値を順守する必要があります。世界保健機関 (WHO) は、公共浄水施設における最高汚染レベルを 10 μg/L と定めています。ヨーロッパのミネラルウォーター中の臭素の最高許容濃度は、3 μg/Lに定められています。これらの値をさらに引き下げることも審議されています。ISO 11206 では、ポストカラム反応後のUV検出を伴うICによる飲料水中の臭素の測定について説明されています。臭素は、酸性溶液中のヨウ化物をヨウ素へと酸化させます。過剰なヨウ化物は、ヨウ素によって、352 nm で吸収する 3ヨウ化イオン (I3-) を形成します。このアプリケーションにより、1 μg/Lまで、およびそれ以下の臭素を定量化することができます。